1. Field of the Invention
This invention relates to turbo-prop powered aircraft.
2. Description of the Prior Art
Conventional wing mounted turbo-prop installations require that powerplants be located in such a way as to minimize the risk of debris, resulting from an uncontained rotor failure for example, penetrating the structural wing box or catastrophically damaging wing attachments. In addition, engine combustion chambers should not be located adjacent to fuel tanks. As a consequence of these requirements wing mounted turbo-prop installations are generally arranged such that all rotating parts are located ahead of the wing leading edge. However, such arrangements may result in excessive overhang and potential flutter problems and would be particularly so in the case of an aircraft powered by contra-rotating propellers where the ratio of overhang to local structural wing box chord is high. It is the object of the present invention to provide an aircraft configuration to overcome these various shortcomings.
GB-A-621,606 and GB-A-621,607 disclose an engine arrangement in which the core engine is separated from the propeller assembly and connected thereto by means of an extended drive shaft. In this arrangement, however, the engines are located in recesses formed within the structural wing box which as already stated is undesirable, with the propeller assembly being a pusher propeller located behind the wing, and this arrangement does not meet the required safety standards in the event of a catastrophic engine failure.